Device for overcoming dead-centers.



No. 653,257. Patented July l0, I900.

J. MARTIN.

DEVICE FDR DVEBDDMING DEAD CENTERS.

(Application filgd Mar. 31, 1900.) (No Model.)

m: Noam: PETERS cu. PHOTO-LITHD,WASNINGYON. n, c.

JAMES MARTIN, QF lIOlV ARD LAKE, MINNESOTA.

DEVICE FOR OVERCOMING DEAD-CENTERS.

SPECIFICATION forming part of Letters Patent No. 653,257, dated July 10, 1900. Application filed March 31,1900. Serial no. 11,009. (No model.)

To all whom it may concern:

Be it known that I, JAMES MARTIN, a citizen of the United States, residing at Howard Lake, in the county of Wright and State of Minnesota, have invented a new and useful Device for Overcoming Dead Centers, of which the following is a specification.

The invention relates to improvements in devices for overcoming dead-centers.

The object of the present invention is to improve the means employed for connecting a reciprocating piston, or rather the pitman thereof, with a crank for converting a reciprocating motion into rotary motion and to provide a simple and comparatively-inexpensive device adapted to overcome the deadcenters of crank motion and capable of enabling the pitman to be arranged in a variety of positions to obtain a stroke of the desired length and direction.

The invention consists in the construction and novel combination and arrangement of parts hereinafter fully described, illustrated in the accompanying drawing, and pointed out in the claims hereto appended.

The figure of the drawing is an elevation of a device for overcoming dead-centers constructed in accordance with this invention.

Referring to the drawing, 1 designates a crank which is connected by a sigmoidallycurved link 2 with one end of a lever 3, and the latter is fulcrumed at its center at l at one side of the crank and has its other end connected by a long link 5 with a long curved link 6. The end 7 of the long curved link 6 is pivoted to the outer end of the crank by the pivot which connects the inner end of the sigmoidally-curved' link 2 with the same. The long curved link 6, which is approximately parallel with the lever when the parts are arranged in the position shown in full lines in the drawing, diverges slightly from the said lever and is pivoted at its outer end 8 to the adjacent end of the long link 5, which is disposed approximately parallel with the short sigmoidally-curved link 2. i

The long link 5 is pivoted between its ends at 9 to the outer end of a pitman 10; but the latter may be connected at different points to the frame formed by the lever 3 and the links, as hereinafter explained. The long curved link 6 has a longitudinal reciprocaand moving in a variety of directions, andthe pitman may be connected with the frame at a variety of points to secure a stroke of the desired length and in the desired direction, and the jointed frame may be supported by a suitable guide 11, which in the accompanying drawing is arranged at an angle to the long links 5 and 6; but its position may be changed to accommodate itself to the arrangement of the pitman.

The end 12of the link 5 is connected by a pivot 13 with the adjacent end 14 of the lever 3, and the said pivot 13 is disposed at a point opposite the central portion of the link 6 or in a plane intersecting such link at a point between the crank and the end 8 of the said link 6. The pivot 9 at the outer end of the pitman 10 travels in an elliptical path,as illustrated in dotted lines in the accompanying drawing.

The jointed frame which forms the connection between the pitman and the crank enables the latter to pass over the dead-centers, and it thereby results in the transmission of a maximum amount of power, and it will also be clear that the arrangement of the members of the jointed frame and the variety of movements resulting from such arrangement will enable the pitman to be arranged in a variety of positions, so that the desired length of stroke and the direction of movement may be readily obtained. Furthermore, it will be apparent that when the piston is at the ends of its stroke the crank will be in approximately a vertical position, as clearly indicated in the drawing, and that when the crank is in a horizontal position the piston will be at an intermediate point of its stroke and will be moving with power and will be capable of cartoo rying the crank beyond such points. The jointed frame also forms a lever connection between the piston and the crank and enables great power to be exerted on the latter.

What is claimed is 1. In a device of the class described, the combination of a crank, the curved link 6 pivoted at its inner end to the outer end of the crank, thelever 3 fulcrumed between its ends and disposed opposite the link 6, the short sigmoidally-bent link 2 connecting one end of the lever with the outer end of the crank, the long slightly-curved link 5 disposed opposite the link 2 and connecting the other end of the lever with the outer end of the link 6, and a pitman connected with one of the links, substantially as described.

2. In a device of the class described, the combination of a crank, the curved link 6 pivoted at its inner end to the outer end of the crank, the lever 3 fulcru med between its ends and disposed opposite the link 6, the short sigmoidally-bent link 2 connecting one end of the lever with the outer end of the crank, the long slightly-curved link 5 disposed opposite the link 2 and connecting the other end of the lever with the outer end of the link 6, a pitman pivotally connected with the link 5, and a guide receiving the links 5 and 6, substantially as described.

In testimony that I claim the foregoing as my own I have hereto affiXed my signature in the presence of two Witnesses.

JAMES MARTIN.

Witnesses:

H. F. RILEY, J. M. WALKER. 

